This title brings together a variety of papers presented at the 9th annual Meso meeting in 2007. The topics selected for Meso 2007 are designed to illustrate the relation of thresholds to multiscaling:

• Flow through capillary tubes in contrast to pipes
• Laminar and turbulent flow transition
• Heat convection of thin wires in contrast to cylinders
• Electrical conductance of macro- and nano-circuits
• Rubbery and glassy polymers
• Single- and poly-crystal behavior
• Strength of wires and round cylindrical bars
• Uni-axial and multi-axial material: linear and non-linear response
• Thin and thick plate behavior
• Brittle and ductile fracture
• Small and large crack growth behavior
• Low and high temperature effects
• Local and global material property characteristics
• Small and large bodies: size and time effects
• Specimen and structure